Effect of atrazine on the diaztrophos associated with corn cultivated on soil from Saldana, Tolima

Abstract

The effect of the herbicide atrazine on the diazotrophic microorganisms associated with rhizosphere soil and roots of a corn cultivated on a clay-loam soil in a greenhouse, Ustropet Fluvaquentic from Saldana (Tolima) was evaluated. 61% of soil isolates and 83% of root isolates presented characteristic cultural growth of whitish pellicle under the surface of the semisolid NFb-malic acid medium. The soil population of diazotrophic microorganisms and the nitrogenase activity were not significantly different between atrazine treatments. The highest values were obtained 45 days after the highest dose ofatrazine (3.0 Kg/ha). Corn roots without treatment had greater values throughout the time tested, but those were not significantly different between the treatments. As a conclusion, there were not effects on the population and the nitrogenase activity of the diazotrophic microorganisms up to 90 days after the application of atrazine.

Keywords

• Trazina
• Bacterias
• Bagazo de Maíz
• Saldaña
• Colombia